- EOL
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Attention! The product has been discontinued. Check other products in category. |
Description
The matrix consists of 16 buttons, type tact switch, distributed in four rows and four columns. The system communicates via an analog signal using only one analog input of the microcontroller. Pins are the popular goldpin connectors - pitch of 2.54 mm.
Connection
The system has three pins: VCC - supply voltage, GND ground and AD, that is, the analog output signal. For information, which button is on, in addition to power supply, AD output should be connected to the input of converter A/C, for example, a pin marked by the letter A inArduino.
The formula to calculate the button number from the value of the read voltage, is as follows:
Viv = (button number / 16) x Vref
where:
Viv- read voltage
Vref- voltage reference (in this case, it is the supply voltage)
The value of the measurement error can be calculated from the formula:
Vrv = (1 +/-6%)* Viv
For example, if you press 8 button, the supply voltage is 5 V, then the read voltage value is 2.5 V with a tolerance of 0.15 V. So the value in the range from 2.35 V to 2.65 V should be accepted.
Table of sample values for each button
| ADC |
Vref=3.3 V |
Vref = 5V |
||||||
|---|---|---|---|---|---|---|---|---|
| No. |
10-bit ADC |
8-bit ADC |
The measured value (V) |
Error (V) |
The perfect value (V) |
The measured value (V) |
Error (V) |
The perfect value (V) |
| 0 | 0-4 | 0-1 | 0 | 0 | 0 | 0 | 0 | 0 |
| 1 |
(1±6%) x64 |
(1±6%) x16 |
0.2054 | -0.00085 | 0.20625 | 0.3112 | -0.0013 | 0.3125 |
| 2 |
(1±6%) x128 |
(1±6%) x32 |
0.4117 | -0.0008 | 0.4125 | 0.6238 | -0.0012 | 0.625 |
| 3 |
(1±6%) x192 |
(1±6%) x48 |
0.6233 | 0.00455 | 0.61875 | 0.9444 | 0.0069 | 0.9375 |
| 4 |
(1±6%) x256 |
(1±6%) x64 |
0.8242 | -0.0008 | 0.825 | 1.2487 | -0.0013 | 1.25 |
| 5 |
(1±6%) x320 |
(1±6%) x80 |
1.0304 | -0.00085 | 1.03125 | 1.5612 | -0.0013 | 1.5625 |
| 6 |
(1±6%) x384 |
(1±6%) x96 |
1.2355 | -0.002 | 1.2375 | 1.8719 | -0.0031 | 1.875 |
| 7 |
(1±6%)x 448 |
(1±6%) x112 |
1.4448 | 0.00105 | 1.44375 | 2.189 | 0.0015 | 2.1875 |
| 8 |
(1±6%) x512 |
(1±6%) x128 |
1.6541 | 0.0041 | 1.65 | 2.5061 | 0.0061 | 2.5 |
| 9 |
(1±6%) x576 |
(1±6%) x144 |
1.8637 | 0.00745 | 1.85625 | 2.8237 | 0.0112 | 2.8125 |
| 10 |
(1±6%) x640 |
(1±6%) x160 |
2.0732 | 0.0107 | 2.0625 | 3.1411 | 0.0161 | 3.125 |
| 11 |
(1±6%) x704 |
(1±6%) x176 |
2.2672 | -0.00155 | 2.26875 | 3.435 | -0.0025 | 3.4375 |
| 12 |
(1±6%) x 768 |
(1±6%) x192 |
2.4712 | -0.0038 | 2.475 | 3.7441 | -0.0059 | 3.75 |
| 13 |
(1±6%) x832 |
(1±6%) x208 |
2.6789 | -0.00235 | 2.68125 | 4.0588 | -0.0037 | 4.0625 |
| 14 |
(1±6%) x896 |
(1±6%) x224 |
2.8902 | 0.0027 | 2.8875 | 4.3789 | 0.0039 | 4.375 |
| 15 |
(1±6%) x960 |
(1±6%) x240 |
3.1092 | 0.01545 | 3.09375 | 4.7107 | 0.0232 | 4.6875 |
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